org.dlese.dpc.util
Class MemoryCheck

java.lang.Object
  org.dlese.dpc.util.MemoryCheck

public class MemoryCheck
extends Object

This class provides a utility to determine how much memory your application is using at any given time. Useful for determining the memory requirements of a given Object and for debugging possible memory leaks. See JavaWorld article for more info. Includes a sample main method that shows how it might be used.

To get a snapshot of current memory first call runGC() and then call getUsedMemory() .

Example code:

MemoryCheck.runGC();
Long currentMem = MemoryCheck.getUsedMemory();

Version:

$Id: MemoryCheck.java,v 1.6 2009/03/20 23:34:00 jweather Exp $

Author:

John Weatherley

Constructor Summary

MemoryCheck()

Method Summary

static String	getDateStamp() Return a string for the current time and date, sutiable for display in log files and output to standout:
static long	getUsedMemory() Gets the current amount of memory being used by this app, in bytes.
static String	getUsedMemoryInMegs() Gets the current amount of memory being used by this app, in megabytes.
static void	main(String[] args) The main program for the MemoryCheck class
static void	runGC() Runs object finization and the garbage collector several times.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MemoryCheck

public MemoryCheck()

Method Detail

main

public static void main(String[] args)
                 throws Exception

The main program for the MemoryCheck class

Parameters:

args - The command line arguments

Throws:

Exception - If error

getUsedMemory

public static long getUsedMemory()

Gets the current amount of memory being used by this app, in bytes. For best accuracy you should call runGC() prior to calling this method.

Returns:

The current amount of memory being used by the JVM.

getUsedMemoryInMegs

public static String getUsedMemoryInMegs()

Gets the current amount of memory being used by this app, in megabytes. For best accuracy you should call runGC() prior to calling this method.

Returns:

The current amount of memory being used by the JVM.

runGC

public static void runGC()

Runs object finization and the garbage collector several times. This tends to be more effective than juse calling garbage collection once.

getDateStamp

public static String getDateStamp()

Return a string for the current time and date, sutiable for display in log files and output to standout:

Returns:

The dateStamp value